<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1, user-scalable=no">
    <meta http-equiv="X-UA-Compatible" content="ie=edge,chrome=1">
    <meta name="author" content="杨宁争">
    <title></title>
    <style>
    .box{
        width: 400px;
        border: 1px solid #000;
        margin:  50px auto;
    }
.tab{
     margin: 0;
    padding: 0;
    list-style: none;
    background-color: greenyellow;
   

}
.tab li{
    float: left;
    width: 100px;
    text-align: center;
    line-height: 36px;
}
.clearfix::after{
           content: '';
            clear: both;
            display: block;
            height: 0;
            visibility: hidden;
}
    </style>
</head>
<body>
<div class="box">
    <ul class="tab">
        <li class="active">新闻</li>
        <li>公告</li>
        <li>赛程</li>
    </ul>
    <div class="content">
 <p>1--新闻<br>新闻<br>新闻<br></p>
 <p>1--新闻<br>新闻<br>新闻<br></p>
 <p>1--新闻<br>新闻<br>新闻<br></p>
    </div>
</div>
</body>
</html>